1. Field of Invention
This invention relates to multilayered boards used for supporting and/or interconnecting various components of an electronic circuit, and more particularly to a method of making a board having a shielded conductor imbedded therein.
2. Description of the Prior Art
Typically miniaturized electronic circuits comprise several components such as transistors, resistors, capacitors, and so on as well as various integrated circuits (I.C.'s) which are mounted on a board. Interconnection between the different components is accomplished by providing a preselected strip pattern on the board by photomasking or other methods. However it is well-known that at high frequencies (i.e. in the Megahertz or Gigahertz range), the inductive and capacitance losses in these wires are prohibitive and furthermore the cross-coupling therebetween cause unacceptable distortions in the signals. Therefore it has been proposed that the components be interconnected by conductors imbedded in the board disposed between two parallel ground planes. However it is found that even with this configuration, cross-coupling between adjacent conductors occurs unless the conductors are spaced far apart. This spacing in turn required a proportionate increase in the size of the boards.